Speaker
Description
In relativistic heavy-ion collisions, the quark-gluon plasma is created, and as the medium cools down, the system transitions into a hadronic phase. While such interactions are well established for large systems, such as Pb-Pb collisions, their relevance in smaller collision systems remains unclear. Therefore, we analyse pp collisions at $\sqrt{s}=13$ TeV and p-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV events using PYTHIA8 at the ALICE acceptance, at midrapidity ($|y|<0.5$). The observable is the yield ratio of short-lived resonances to their stable counterparts as a function of $p_\mathrm{T}$: $\rho(770)^0/\pi^\pm$, $\mathrm{K^*(892)^0/K^\pm}$, and $\mathrm{\phi(1020)/K^\pm}$. Ratios are reported in five (pp) and six (p-Pb) multiplicity classes, referenced to pp 60-100\%. Turning hadronic rescattering on yields stronger suppression at low $p_\mathrm{T}$($<2$ GeV/$c$); however, a visible suppression persists even with rescattering off. To isolate rescattering, we form double ratios (on/off), then integrate over $0<p_\mathrm{T}<6.0$ GeV/$c$. The normalised double ratios decrease with increasing multiplicity, similarly in pp and p-Pb. From the integrated ratios, the lower limit of the hadronic phase lifetime increases with multiplicity in both systems, with a notable pp and p-Pb discrepancy. This poster aims to study hadronic phase effects in small systems via resonance-to-stable yield ratios and rescattering-sensitive double ratios, and to quantify the multiplicity dependence of the hadronic phase lifetime in pp and p-Pb collisions.
